1. Field of the Invention
This invention relates to edge protectors for protecting goods having at least one edge against damage of the edge by a strap wrapping the goods and more particularly to a novel and highly effective edge protector constructed to prevent its inadvertent detachment from the wrapping strap even upon removal of the strap from the goods.
2. Description of the Prior Art
When certain goods are packaged for handling in a warehouse or for shipment they are often banded with a steel or plastic strap or tether. The goods may be stacked on a wooden, metal or plastic pallet, and several straps are passed through or around the pallet and around the goods to secure the goods so that they can be handled safely by a forklift or crane and thereby moved around a warehouse, loaded into a standard 20 foot or 40 foot container, or lowered into the hold of a ship.
Roll goods such as paper or sheet steel are often secured by wrapping straps extending longitudinally through the center and along the outside of the roll and radially along opposite ends of the roll.
In order to ensure that the goods are held securely, the bands are tightened with a considerable force, usually generated by a banding machine or similar equipment. The force supplied by a banding strap to the goods is highly concentrated where the strap bears against an edge of the banded goods, and to prevent damage to the edge of the goods, an edge protector is employed. Edge protectors are placed between the straps and the edges of the goods, and the straps bear on the edge protectors instead of directly on the banded goods.
An edge protector includes a plate or similar structure to distribute over a relatively large area the force that would otherwise be applied directly to a small part of an edge.
Conventional edge protectors, however, have some inconvenient aspects. One is that they are awkward to put into service.
Certain edge protectors are for example put into service by threading an end of a banding strap through a first aperture in the edge protector from the bottom side to the top side of the edge protector, passing it over the top of the edge protector, and threading it through a second aperture from the top side to the bottom side. The part of the edge protector between the two apertures is placed over an edge to be protected. In many facilities, hundreds of edge protectors are used per day, and the aggregate time devoted to the threading operation is considerable and adds commensurately to the cost of handling the goods.
Another type of conventional edge protector is provided with tabs that can be raised by hand to accept a banding strap and then lowered on the strap to connect the edge protector and the strap together. This has the advantage that the strap can be connected to the edge protector by a relative lateral movement; in other words, it is not necessary to thread the end of the strap through an aperture. However, it is awkward to raise the tabs by hand while engaging the straps; typically one or more digits of one hand must push down on a first part of the edge protector and one or more digits of the same hand must pull up on another part of the edge protector while the other hand inserts the strap. This requires enough manual dexterity that some people find it objectionable and accomplish it only with difficulty. Even those who are quite dextrous find that a certain amount of time and patience is required to accomplish the task. If the task must be repeated hundreds of time in an eighthour work shift, there is some risk of developing tunnel carpel syndrome or other injury due to repetitive motion.
U.S. Pat. No. 3,073,439 discloses an edge protector having an opening 30 so that masking tape 32 (FIG. 2) can be employed to prevent the edge protector from moving relative to the protected goods. In the modification of FIG. 5, an adhesive patch 134 is employed.
U.S. Pat. No. 3,152,693 discloses an edge protector having tabs 15 that can be manually pivoted about flexible hinges 16 to accept a strap 13. When the strap 13 is inserted, the tabs 15 prevent it from becoming dislodged.
U.S. Pat. No. 3,908,850 discloses a protector having shoulders 32 that position it with respect to a strap 20 and teeth 38 for securing it to a wooden crate or the like.
U.S. Pat. No. 3,960,091 discloses a rope hook mount having a lip 17 formed with a free end 20 extending over a central aperture 16 so that a rope 19 can be anchored under the lip 17 and used to stabilize cargo in a vehicle such as a truck or boat.
U.S Pat. No. 4,011,632 discloses a protector having a lip 28 that can be slipped between adjacent cartons 14 in a stack of cartons.
U S. Pat. No. 4,938,357 discloses an edge protector formed with a slot 9 for a strap 2 and with a tab 12 that extends over the strap 2. However, the tab 12 is not formed with a cam at its distal end. Moreover, the strap 2 does not overlie any part of the arm 6 between the slot 9 and the edge 10. While this device may stay attached to the strap 2 after the strap 2 is cut, the method of attachment is relatively cumbersome and requires that the tab 12 be bent out manually to receive the strap 2 or that the strap 2 be threaded through the slot 9 from the bottom.
U.S. Pat. No. 5,056,664 discloses an edge protector formed with openings 14 and 15 so that a tether 17 can be passed through the openings to secure the protector to a stack 16. While the strip 11 will not separate from the tether 17 when the tether 17 is cut, the tether 17 can be secured to the strip 11 only by threading it through the openings 14 and 15, which is a relatively cumbersome procedure.